---
title: Save and Restore States
description: Learn to save and restore AI and UI states with onGetUIState and onSetAIState using the Vercel AI SDK in your Next.js App Router application
---

# Save and Restore AI State

Sometimes conversations with language models can get interesting and you might want to save the state of so you can revisit it or continue the conversation later.

`createAI` has an experimental callback function called `unstable_onSetAI` that gets called whenever the AI state changes. You can use this to save the AI state to a filename or a database.

## Client

```tsx filename='app/layout.tsx'
import { AI, ServerMessage } from './actions';

export default function RootLayout({
  children,
}: Readonly<{
  children: React.ReactNode;
}>) {
  // get chat history from database
  const history: ServerMessage[] = getChat();

  return (
    <html lang="en">
      <body>
        <AI initialAIState={history} initialUIState={[]}>
          {children}
        </AI>
      </body>
    </html>
  );
}
```

```tsx filename='app/page.tsx'
'use client';

import { useState } from 'react';
import { ClientMessage } from './actions';
import { useActions, useUIState } from 'ai/rsc';
import { generateId } from 'ai';

// Force the page to be dynamic and allow streaming responses up to 30 seconds
export const dynamic = 'force-dynamic';
export const maxDuration = 30;

export default function Home() {
  const [input, setInput] = useState<string>('');
  const [conversation, setConversation] = useUIState();
  const { continueConversation } = useActions();

  return (
    <div>
      <div>
        {conversation.map((message: ClientMessage) => (
          <div key={message.id}>
            {message.role}: {message.display}
          </div>
        ))}
      </div>

      <div>
        <input
          type="text"
          value={input}
          onChange={event => {
            setInput(event.target.value);
          }}
        />
        <button
          onClick={async () => {
            setConversation((currentConversation: ClientMessage[]) => [
              ...currentConversation,
              { id: generateId(), role: 'user', display: input },
            ]);

            const message = await continueConversation(input);

            setConversation((currentConversation: ClientMessage[]) => [
              ...currentConversation,
              message,
            ]);
          }}
        >
          Send Message
        </button>
      </div>
    </div>
  );
}
```

## Server

We will use the callback function to listen to state changes and save the conversation once we receive a `done` event.

```tsx filename='app/actions.tsx'
'use server';

import { createAI, getAIState, getMutableAIState, streamUI } from 'ai/rsc';
import { openai } from '@ai-sdk/openai';
import { ReactNode } from 'react';
import { z } from 'zod';
import { generateId } from 'ai';
import { Stock } from '@ai-studio/components/stock';

export interface ServerMessage {
  role: 'user' | 'assistant' | 'function';
  content: string;
}

export interface ClientMessage {
  id: string;
  role: 'user' | 'assistant' | 'function';
  display: ReactNode;
}

export async function continueConversation(
  input: string,
): Promise<ClientMessage> {
  'use server';

  const history = getMutableAIState();

  const result = await streamUI({
    model: openai('gpt-3.5-turbo'),
    messages: [...history.get(), { role: 'user', content: input }],
    text: ({ content, done }) => {
      if (done) {
        history.done((messages: ServerMessage[]) => [
          ...messages,
          { role: 'user', content: input },
          { role: 'assistant', content },
        ]);
      }

      return <div>{content}</div>;
    },
    tools: {
      showStockInformation: {
        description:
          'Get stock information for symbol for the last numOfMonths months',
        parameters: z.object({
          symbol: z
            .string()
            .describe('The stock symbol to get information for'),
          numOfMonths: z
            .number()
            .describe('The number of months to get historical information for'),
        }),
        generate: async ({ symbol, numOfMonths }) => {
          history.done((messages: ServerMessage[]) => [
            ...messages,
            {
              role: 'function',
              name: 'showStockInformation',
              content: JSON.stringify({ symbol, numOfMonths }),
            },
          ]);

          return <Stock symbol={symbol} numOfMonths={numOfMonths} />;
        },
      },
    },
  });

  return {
    id: generateId(),
    role: 'assistant',
    display: result.value,
  };
}

export const AI = createAI<ServerMessage[], ClientMessage[]>({
  actions: {
    continueConversation,
  },
  unstable_onSetAIState: async ({ state, done }) => {
    'use server';

    if (done) {
      saveChat(state);
    }
  },
  unstable_onGetUIState: async () => {
    'use server';

    const history: ServerMessage[] = getAIState();

    return history.map(({ role, content }) => ({
      id: generateId(),
      role,
      display:
        role === 'function' ? <Stock {...JSON.parse(content)} /> : content,
    }));
  },
});
```
